<template>
  <div class='com-container'>
    <div class='com-chart' ref='stock_ref'></div>
  </div>
</template>

<script>
import axios from 'axios'
export default {
  data () {
    return {
      chartInstance: null,
      allData: null,
      currentIndex: 0, // 当前显示的数据
      timerId: null, // 定时器ID标识
    }
  },
  mounted () {
    this.initChart()
    this.getData()
    window.addEventListener('resize', this.screenAdapter)
    this.screenAdapter()
  },
  destroyed () {
    window.removeEventListener('resize', this.screenAdapter)
    clearInterval(this.timerId)
  },
  methods: {
    async initChart () {
      this.chartInstance = this.$echarts.init(this.$refs.stock_ref, 'chalk')
      const initOption = {
        title: {
          text: '| 库存和销量的分析',
          left: 20,
          top: 20
        }

      }
      this.chartInstance.setOption(initOption)
      this.chartInstance.on('mouseover',()=>{
        clearInterval(this.timerId)
      })
      this.chartInstance.on('mouseout',()=>{
        this.startInterval()
      })
    },
    async getData () {
      // 获取服务器的数据, 对this.allData进行赋值之后, 调用updateChart方法更新图表
      const { data: ret } = await this.$http.get('stock')
      this.allData = ret
      console.log(this.allData)
      this.updateChart()
      this.startInterval()
    },
    updateChart () {
      const centerArr = [
        ['18%', '40%'],
        ['50%', '40%'],
        ['82%', '40%'],
        ['34%', '75%'],
        ['66%', '75%']
      ]
      const colorArr = [
        ['#4FF778', '#0BA82C'],
        ['#E5DD45', '#E8B11C'],
        ['#E8821C', '#E55445'],
        ['#5052EE', '#AB6EE5'],
        ['#23E5E5', '#2E72BF']
      ]
      // 处理图表需要的数据
      const start = this.currentIndex * 5
      const end = (this.currentIndex + 1) * 5
      const showData = this.allData.slice(start, end)
      const seriesData = showData.map((item, index) => {
        return {
          type: 'pie',
          radius: [110, 100],
          center: centerArr[index], // 饼图在屏幕中的位置
          hoverAnimation: false, // 关闭鼠标移入到饼图时的动画效果
          labelLine:{
            show: false
          },
          label: {
            position: 'center',
            color: colorArr[index][0],
          },
          data: [
            {
                name: item.name + '\n' + item.sales,
                value: item.sales,
                itemStyle: {
                    color: new this.$echarts.graphic.LinearGradient(0, 1, 0, 0, [
                        {
                            offset: 0,
                            color: colorArr[index][0]
                        },
                        {
                            offset: 1,
                            color: colorArr[index][1]
                        }
                    ])
                }
            },
            {
                value: item.stock,
                itemStyle: {
                    color: '#333843'
                }
            }
          ]
        }
      })
      // 图例的数据
      const dataOption = {
        series: seriesData
      }
      this.chartInstance.setOption(dataOption)
    },
    screenAdapter () {
      const titleFontSize = this.$refs.stock_ref.offsetWidth / 100 * 3.6
      const innerRadius = titleFontSize * 2
      const outerRadius = innerRadius * 1.125
      const adapterOption = {
        title: {
          textStyle: {
            fontSize: titleFontSize
          }
        },
        series: [
          {
            type: 'pie',
            radius: [outerRadius, innerRadius],
            label: {
              fontSize: titleFontSize / 2
            }
          },
          {
            type: 'pie',
            radius: [outerRadius, innerRadius],
            label: {
              fontSize: titleFontSize / 2
            }
          },
          {
            type: 'pie',
            radius: [outerRadius, innerRadius],
            label: {
              fontSize: titleFontSize / 2
            }
          },
          {
            type: 'pie',
            radius: [outerRadius, innerRadius],
            label: {
              fontSize: titleFontSize / 2
            }
          },
          {
            type: 'pie',
            radius: [outerRadius, innerRadius],
            label: {
              fontSize: titleFontSize / 2
            }
          }

        ]
      }
      this.chartInstance.setOption(adapterOption)
      this.chartInstance.resize()
    },
    startInterval () {
        if (this.timerId) {
          clearInterval(this.timerId)
        }
        this.timerId = setInterval(() => {
            this.currentIndex++
            if (this.currentIndex > 1) {
                this.currentIndex = 0
            }
            this.updateChart() // 更新图表
            this.screenAdapter()  // 适配屏幕
        }, 5000)
    },
  }
}
</script>

<style lang='less' scoped>
</style>